1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * udlfb.c -- Framebuffer driver for DisplayLink USB controller 4 * 5 * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it> 6 * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com> 7 * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com> 8 * 9 * Layout is based on skeletonfb by James Simmons and Geert Uytterhoeven, 10 * usb-skeleton by GregKH. 11 * 12 * Device-specific portions based on information from Displaylink, with work 13 * from Florian Echtler, Henrik Bjerregaard Pedersen, and others. 14 */ 15 16 #include <linux/module.h> 17 #include <linux/kernel.h> 18 #include <linux/init.h> 19 #include <linux/usb.h> 20 #include <linux/uaccess.h> 21 #include <linux/mm.h> 22 #include <linux/fb.h> 23 #include <linux/vmalloc.h> 24 #include <linux/slab.h> 25 #include <linux/delay.h> 26 #include <asm/unaligned.h> 27 #include <video/udlfb.h> 28 #include "edid.h" 29 30 static const struct fb_fix_screeninfo dlfb_fix = { 31 .id = "udlfb", 32 .type = FB_TYPE_PACKED_PIXELS, 33 .visual = FB_VISUAL_TRUECOLOR, 34 .xpanstep = 0, 35 .ypanstep = 0, 36 .ywrapstep = 0, 37 .accel = FB_ACCEL_NONE, 38 }; 39 40 static const u32 udlfb_info_flags = FBINFO_DEFAULT | FBINFO_READS_FAST | 41 FBINFO_VIRTFB | 42 FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT | 43 FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR; 44 45 /* 46 * There are many DisplayLink-based graphics products, all with unique PIDs. 47 * So we match on DisplayLink's VID + Vendor-Defined Interface Class (0xff) 48 * We also require a match on SubClass (0x00) and Protocol (0x00), 49 * which is compatible with all known USB 2.0 era graphics chips and firmware, 50 * but allows DisplayLink to increment those for any future incompatible chips 51 */ 52 static const struct usb_device_id id_table[] = { 53 {.idVendor = 0x17e9, 54 .bInterfaceClass = 0xff, 55 .bInterfaceSubClass = 0x00, 56 .bInterfaceProtocol = 0x00, 57 .match_flags = USB_DEVICE_ID_MATCH_VENDOR | 58 USB_DEVICE_ID_MATCH_INT_CLASS | 59 USB_DEVICE_ID_MATCH_INT_SUBCLASS | 60 USB_DEVICE_ID_MATCH_INT_PROTOCOL, 61 }, 62 {}, 63 }; 64 MODULE_DEVICE_TABLE(usb, id_table); 65 66 /* module options */ 67 static bool console = true; /* Allow fbcon to open framebuffer */ 68 static bool fb_defio = true; /* Detect mmap writes using page faults */ 69 static bool shadow = true; /* Optionally disable shadow framebuffer */ 70 static int pixel_limit; /* Optionally force a pixel resolution limit */ 71 72 struct dlfb_deferred_free { 73 struct list_head list; 74 void *mem; 75 }; 76 77 static int dlfb_realloc_framebuffer(struct dlfb_data *dlfb, struct fb_info *info, u32 new_len); 78 79 /* dlfb keeps a list of urbs for efficient bulk transfers */ 80 static void dlfb_urb_completion(struct urb *urb); 81 static struct urb *dlfb_get_urb(struct dlfb_data *dlfb); 82 static int dlfb_submit_urb(struct dlfb_data *dlfb, struct urb * urb, size_t len); 83 static int dlfb_alloc_urb_list(struct dlfb_data *dlfb, int count, size_t size); 84 static void dlfb_free_urb_list(struct dlfb_data *dlfb); 85 86 /* 87 * All DisplayLink bulk operations start with 0xAF, followed by specific code 88 * All operations are written to buffers which then later get sent to device 89 */ 90 static char *dlfb_set_register(char *buf, u8 reg, u8 val) 91 { 92 *buf++ = 0xAF; 93 *buf++ = 0x20; 94 *buf++ = reg; 95 *buf++ = val; 96 return buf; 97 } 98 99 static char *dlfb_vidreg_lock(char *buf) 100 { 101 return dlfb_set_register(buf, 0xFF, 0x00); 102 } 103 104 static char *dlfb_vidreg_unlock(char *buf) 105 { 106 return dlfb_set_register(buf, 0xFF, 0xFF); 107 } 108 109 /* 110 * Map FB_BLANK_* to DisplayLink register 111 * DLReg FB_BLANK_* 112 * ----- ----------------------------- 113 * 0x00 FB_BLANK_UNBLANK (0) 114 * 0x01 FB_BLANK (1) 115 * 0x03 FB_BLANK_VSYNC_SUSPEND (2) 116 * 0x05 FB_BLANK_HSYNC_SUSPEND (3) 117 * 0x07 FB_BLANK_POWERDOWN (4) Note: requires modeset to come back 118 */ 119 static char *dlfb_blanking(char *buf, int fb_blank) 120 { 121 u8 reg; 122 123 switch (fb_blank) { 124 case FB_BLANK_POWERDOWN: 125 reg = 0x07; 126 break; 127 case FB_BLANK_HSYNC_SUSPEND: 128 reg = 0x05; 129 break; 130 case FB_BLANK_VSYNC_SUSPEND: 131 reg = 0x03; 132 break; 133 case FB_BLANK_NORMAL: 134 reg = 0x01; 135 break; 136 default: 137 reg = 0x00; 138 } 139 140 buf = dlfb_set_register(buf, 0x1F, reg); 141 142 return buf; 143 } 144 145 static char *dlfb_set_color_depth(char *buf, u8 selection) 146 { 147 return dlfb_set_register(buf, 0x00, selection); 148 } 149 150 static char *dlfb_set_base16bpp(char *wrptr, u32 base) 151 { 152 /* the base pointer is 16 bits wide, 0x20 is hi byte. */ 153 wrptr = dlfb_set_register(wrptr, 0x20, base >> 16); 154 wrptr = dlfb_set_register(wrptr, 0x21, base >> 8); 155 return dlfb_set_register(wrptr, 0x22, base); 156 } 157 158 /* 159 * DisplayLink HW has separate 16bpp and 8bpp framebuffers. 160 * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer 161 */ 162 static char *dlfb_set_base8bpp(char *wrptr, u32 base) 163 { 164 wrptr = dlfb_set_register(wrptr, 0x26, base >> 16); 165 wrptr = dlfb_set_register(wrptr, 0x27, base >> 8); 166 return dlfb_set_register(wrptr, 0x28, base); 167 } 168 169 static char *dlfb_set_register_16(char *wrptr, u8 reg, u16 value) 170 { 171 wrptr = dlfb_set_register(wrptr, reg, value >> 8); 172 return dlfb_set_register(wrptr, reg+1, value); 173 } 174 175 /* 176 * This is kind of weird because the controller takes some 177 * register values in a different byte order than other registers. 178 */ 179 static char *dlfb_set_register_16be(char *wrptr, u8 reg, u16 value) 180 { 181 wrptr = dlfb_set_register(wrptr, reg, value); 182 return dlfb_set_register(wrptr, reg+1, value >> 8); 183 } 184 185 /* 186 * LFSR is linear feedback shift register. The reason we have this is 187 * because the display controller needs to minimize the clock depth of 188 * various counters used in the display path. So this code reverses the 189 * provided value into the lfsr16 value by counting backwards to get 190 * the value that needs to be set in the hardware comparator to get the 191 * same actual count. This makes sense once you read above a couple of 192 * times and think about it from a hardware perspective. 193 */ 194 static u16 dlfb_lfsr16(u16 actual_count) 195 { 196 u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */ 197 198 while (actual_count--) { 199 lv = ((lv << 1) | 200 (((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1)) 201 & 0xFFFF; 202 } 203 204 return (u16) lv; 205 } 206 207 /* 208 * This does LFSR conversion on the value that is to be written. 209 * See LFSR explanation above for more detail. 210 */ 211 static char *dlfb_set_register_lfsr16(char *wrptr, u8 reg, u16 value) 212 { 213 return dlfb_set_register_16(wrptr, reg, dlfb_lfsr16(value)); 214 } 215 216 /* 217 * This takes a standard fbdev screeninfo struct and all of its monitor mode 218 * details and converts them into the DisplayLink equivalent register commands. 219 */ 220 static char *dlfb_set_vid_cmds(char *wrptr, struct fb_var_screeninfo *var) 221 { 222 u16 xds, yds; 223 u16 xde, yde; 224 u16 yec; 225 226 /* x display start */ 227 xds = var->left_margin + var->hsync_len; 228 wrptr = dlfb_set_register_lfsr16(wrptr, 0x01, xds); 229 /* x display end */ 230 xde = xds + var->xres; 231 wrptr = dlfb_set_register_lfsr16(wrptr, 0x03, xde); 232 233 /* y display start */ 234 yds = var->upper_margin + var->vsync_len; 235 wrptr = dlfb_set_register_lfsr16(wrptr, 0x05, yds); 236 /* y display end */ 237 yde = yds + var->yres; 238 wrptr = dlfb_set_register_lfsr16(wrptr, 0x07, yde); 239 240 /* x end count is active + blanking - 1 */ 241 wrptr = dlfb_set_register_lfsr16(wrptr, 0x09, 242 xde + var->right_margin - 1); 243 244 /* libdlo hardcodes hsync start to 1 */ 245 wrptr = dlfb_set_register_lfsr16(wrptr, 0x0B, 1); 246 247 /* hsync end is width of sync pulse + 1 */ 248 wrptr = dlfb_set_register_lfsr16(wrptr, 0x0D, var->hsync_len + 1); 249 250 /* hpixels is active pixels */ 251 wrptr = dlfb_set_register_16(wrptr, 0x0F, var->xres); 252 253 /* yendcount is vertical active + vertical blanking */ 254 yec = var->yres + var->upper_margin + var->lower_margin + 255 var->vsync_len; 256 wrptr = dlfb_set_register_lfsr16(wrptr, 0x11, yec); 257 258 /* libdlo hardcodes vsync start to 0 */ 259 wrptr = dlfb_set_register_lfsr16(wrptr, 0x13, 0); 260 261 /* vsync end is width of vsync pulse */ 262 wrptr = dlfb_set_register_lfsr16(wrptr, 0x15, var->vsync_len); 263 264 /* vpixels is active pixels */ 265 wrptr = dlfb_set_register_16(wrptr, 0x17, var->yres); 266 267 /* convert picoseconds to 5kHz multiple for pclk5k = x * 1E12/5k */ 268 wrptr = dlfb_set_register_16be(wrptr, 0x1B, 269 200*1000*1000/var->pixclock); 270 271 return wrptr; 272 } 273 274 /* 275 * This takes a standard fbdev screeninfo struct that was fetched or prepared 276 * and then generates the appropriate command sequence that then drives the 277 * display controller. 278 */ 279 static int dlfb_set_video_mode(struct dlfb_data *dlfb, 280 struct fb_var_screeninfo *var) 281 { 282 char *buf; 283 char *wrptr; 284 int retval; 285 int writesize; 286 struct urb *urb; 287 288 if (!atomic_read(&dlfb->usb_active)) 289 return -EPERM; 290 291 urb = dlfb_get_urb(dlfb); 292 if (!urb) 293 return -ENOMEM; 294 295 buf = (char *) urb->transfer_buffer; 296 297 /* 298 * This first section has to do with setting the base address on the 299 * controller * associated with the display. There are 2 base 300 * pointers, currently, we only * use the 16 bpp segment. 301 */ 302 wrptr = dlfb_vidreg_lock(buf); 303 wrptr = dlfb_set_color_depth(wrptr, 0x00); 304 /* set base for 16bpp segment to 0 */ 305 wrptr = dlfb_set_base16bpp(wrptr, 0); 306 /* set base for 8bpp segment to end of fb */ 307 wrptr = dlfb_set_base8bpp(wrptr, dlfb->info->fix.smem_len); 308 309 wrptr = dlfb_set_vid_cmds(wrptr, var); 310 wrptr = dlfb_blanking(wrptr, FB_BLANK_UNBLANK); 311 wrptr = dlfb_vidreg_unlock(wrptr); 312 313 writesize = wrptr - buf; 314 315 retval = dlfb_submit_urb(dlfb, urb, writesize); 316 317 dlfb->blank_mode = FB_BLANK_UNBLANK; 318 319 return retval; 320 } 321 322 static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma) 323 { 324 unsigned long start = vma->vm_start; 325 unsigned long size = vma->vm_end - vma->vm_start; 326 unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; 327 unsigned long page, pos; 328 329 if (info->fbdefio) 330 return fb_deferred_io_mmap(info, vma); 331 332 if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) 333 return -EINVAL; 334 if (size > info->fix.smem_len) 335 return -EINVAL; 336 if (offset > info->fix.smem_len - size) 337 return -EINVAL; 338 339 pos = (unsigned long)info->fix.smem_start + offset; 340 341 dev_dbg(info->dev, "mmap() framebuffer addr:%lu size:%lu\n", 342 pos, size); 343 344 while (size > 0) { 345 page = vmalloc_to_pfn((void *)pos); 346 if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) 347 return -EAGAIN; 348 349 start += PAGE_SIZE; 350 pos += PAGE_SIZE; 351 if (size > PAGE_SIZE) 352 size -= PAGE_SIZE; 353 else 354 size = 0; 355 } 356 357 return 0; 358 } 359 360 /* 361 * Trims identical data from front and back of line 362 * Sets new front buffer address and width 363 * And returns byte count of identical pixels 364 * Assumes CPU natural alignment (unsigned long) 365 * for back and front buffer ptrs and width 366 */ 367 static int dlfb_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes) 368 { 369 int j, k; 370 const unsigned long *back = (const unsigned long *) bback; 371 const unsigned long *front = (const unsigned long *) *bfront; 372 const int width = *width_bytes / sizeof(unsigned long); 373 int identical; 374 int start = width; 375 int end = width; 376 377 for (j = 0; j < width; j++) { 378 if (back[j] != front[j]) { 379 start = j; 380 break; 381 } 382 } 383 384 for (k = width - 1; k > j; k--) { 385 if (back[k] != front[k]) { 386 end = k+1; 387 break; 388 } 389 } 390 391 identical = start + (width - end); 392 *bfront = (u8 *) &front[start]; 393 *width_bytes = (end - start) * sizeof(unsigned long); 394 395 return identical * sizeof(unsigned long); 396 } 397 398 /* 399 * Render a command stream for an encoded horizontal line segment of pixels. 400 * 401 * A command buffer holds several commands. 402 * It always begins with a fresh command header 403 * (the protocol doesn't require this, but we enforce it to allow 404 * multiple buffers to be potentially encoded and sent in parallel). 405 * A single command encodes one contiguous horizontal line of pixels 406 * 407 * The function relies on the client to do all allocation, so that 408 * rendering can be done directly to output buffers (e.g. USB URBs). 409 * The function fills the supplied command buffer, providing information 410 * on where it left off, so the client may call in again with additional 411 * buffers if the line will take several buffers to complete. 412 * 413 * A single command can transmit a maximum of 256 pixels, 414 * regardless of the compression ratio (protocol design limit). 415 * To the hardware, 0 for a size byte means 256 416 * 417 * Rather than 256 pixel commands which are either rl or raw encoded, 418 * the rlx command simply assumes alternating raw and rl spans within one cmd. 419 * This has a slightly larger header overhead, but produces more even results. 420 * It also processes all data (read and write) in a single pass. 421 * Performance benchmarks of common cases show it having just slightly better 422 * compression than 256 pixel raw or rle commands, with similar CPU consumpion. 423 * But for very rl friendly data, will compress not quite as well. 424 */ 425 static void dlfb_compress_hline( 426 const uint16_t **pixel_start_ptr, 427 const uint16_t *const pixel_end, 428 uint32_t *device_address_ptr, 429 uint8_t **command_buffer_ptr, 430 const uint8_t *const cmd_buffer_end, 431 unsigned long back_buffer_offset, 432 int *ident_ptr) 433 { 434 const uint16_t *pixel = *pixel_start_ptr; 435 uint32_t dev_addr = *device_address_ptr; 436 uint8_t *cmd = *command_buffer_ptr; 437 438 while ((pixel_end > pixel) && 439 (cmd_buffer_end - MIN_RLX_CMD_BYTES > cmd)) { 440 uint8_t *raw_pixels_count_byte = NULL; 441 uint8_t *cmd_pixels_count_byte = NULL; 442 const uint16_t *raw_pixel_start = NULL; 443 const uint16_t *cmd_pixel_start, *cmd_pixel_end = NULL; 444 445 if (back_buffer_offset && 446 *pixel == *(u16 *)((u8 *)pixel + back_buffer_offset)) { 447 pixel++; 448 dev_addr += BPP; 449 (*ident_ptr)++; 450 continue; 451 } 452 453 *cmd++ = 0xAF; 454 *cmd++ = 0x6B; 455 *cmd++ = dev_addr >> 16; 456 *cmd++ = dev_addr >> 8; 457 *cmd++ = dev_addr; 458 459 cmd_pixels_count_byte = cmd++; /* we'll know this later */ 460 cmd_pixel_start = pixel; 461 462 raw_pixels_count_byte = cmd++; /* we'll know this later */ 463 raw_pixel_start = pixel; 464 465 cmd_pixel_end = pixel + min3(MAX_CMD_PIXELS + 1UL, 466 (unsigned long)(pixel_end - pixel), 467 (unsigned long)(cmd_buffer_end - 1 - cmd) / BPP); 468 469 if (back_buffer_offset) { 470 /* note: the framebuffer may change under us, so we must test for underflow */ 471 while (cmd_pixel_end - 1 > pixel && 472 *(cmd_pixel_end - 1) == *(u16 *)((u8 *)(cmd_pixel_end - 1) + back_buffer_offset)) 473 cmd_pixel_end--; 474 } 475 476 while (pixel < cmd_pixel_end) { 477 const uint16_t * const repeating_pixel = pixel; 478 u16 pixel_value = *pixel; 479 480 put_unaligned_be16(pixel_value, cmd); 481 if (back_buffer_offset) 482 *(u16 *)((u8 *)pixel + back_buffer_offset) = pixel_value; 483 cmd += 2; 484 pixel++; 485 486 if (unlikely((pixel < cmd_pixel_end) && 487 (*pixel == pixel_value))) { 488 /* go back and fill in raw pixel count */ 489 *raw_pixels_count_byte = ((repeating_pixel - 490 raw_pixel_start) + 1) & 0xFF; 491 492 do { 493 if (back_buffer_offset) 494 *(u16 *)((u8 *)pixel + back_buffer_offset) = pixel_value; 495 pixel++; 496 } while ((pixel < cmd_pixel_end) && 497 (*pixel == pixel_value)); 498 499 /* immediately after raw data is repeat byte */ 500 *cmd++ = ((pixel - repeating_pixel) - 1) & 0xFF; 501 502 /* Then start another raw pixel span */ 503 raw_pixel_start = pixel; 504 raw_pixels_count_byte = cmd++; 505 } 506 } 507 508 if (pixel > raw_pixel_start) { 509 /* finalize last RAW span */ 510 *raw_pixels_count_byte = (pixel-raw_pixel_start) & 0xFF; 511 } else { 512 /* undo unused byte */ 513 cmd--; 514 } 515 516 *cmd_pixels_count_byte = (pixel - cmd_pixel_start) & 0xFF; 517 dev_addr += (u8 *)pixel - (u8 *)cmd_pixel_start; 518 } 519 520 if (cmd_buffer_end - MIN_RLX_CMD_BYTES <= cmd) { 521 /* Fill leftover bytes with no-ops */ 522 if (cmd_buffer_end > cmd) 523 memset(cmd, 0xAF, cmd_buffer_end - cmd); 524 cmd = (uint8_t *) cmd_buffer_end; 525 } 526 527 *command_buffer_ptr = cmd; 528 *pixel_start_ptr = pixel; 529 *device_address_ptr = dev_addr; 530 } 531 532 /* 533 * There are 3 copies of every pixel: The front buffer that the fbdev 534 * client renders to, the actual framebuffer across the USB bus in hardware 535 * (that we can only write to, slowly, and can never read), and (optionally) 536 * our shadow copy that tracks what's been sent to that hardware buffer. 537 */ 538 static int dlfb_render_hline(struct dlfb_data *dlfb, struct urb **urb_ptr, 539 const char *front, char **urb_buf_ptr, 540 u32 byte_offset, u32 byte_width, 541 int *ident_ptr, int *sent_ptr) 542 { 543 const u8 *line_start, *line_end, *next_pixel; 544 u32 dev_addr = dlfb->base16 + byte_offset; 545 struct urb *urb = *urb_ptr; 546 u8 *cmd = *urb_buf_ptr; 547 u8 *cmd_end = (u8 *) urb->transfer_buffer + urb->transfer_buffer_length; 548 unsigned long back_buffer_offset = 0; 549 550 line_start = (u8 *) (front + byte_offset); 551 next_pixel = line_start; 552 line_end = next_pixel + byte_width; 553 554 if (dlfb->backing_buffer) { 555 int offset; 556 const u8 *back_start = (u8 *) (dlfb->backing_buffer 557 + byte_offset); 558 559 back_buffer_offset = (unsigned long)back_start - (unsigned long)line_start; 560 561 *ident_ptr += dlfb_trim_hline(back_start, &next_pixel, 562 &byte_width); 563 564 offset = next_pixel - line_start; 565 line_end = next_pixel + byte_width; 566 dev_addr += offset; 567 back_start += offset; 568 line_start += offset; 569 } 570 571 while (next_pixel < line_end) { 572 573 dlfb_compress_hline((const uint16_t **) &next_pixel, 574 (const uint16_t *) line_end, &dev_addr, 575 (u8 **) &cmd, (u8 *) cmd_end, back_buffer_offset, 576 ident_ptr); 577 578 if (cmd >= cmd_end) { 579 int len = cmd - (u8 *) urb->transfer_buffer; 580 if (dlfb_submit_urb(dlfb, urb, len)) 581 return 1; /* lost pixels is set */ 582 *sent_ptr += len; 583 urb = dlfb_get_urb(dlfb); 584 if (!urb) 585 return 1; /* lost_pixels is set */ 586 *urb_ptr = urb; 587 cmd = urb->transfer_buffer; 588 cmd_end = &cmd[urb->transfer_buffer_length]; 589 } 590 } 591 592 *urb_buf_ptr = cmd; 593 594 return 0; 595 } 596 597 static int dlfb_handle_damage(struct dlfb_data *dlfb, int x, int y, int width, int height) 598 { 599 int i, ret; 600 char *cmd; 601 cycles_t start_cycles, end_cycles; 602 int bytes_sent = 0; 603 int bytes_identical = 0; 604 struct urb *urb; 605 int aligned_x; 606 607 start_cycles = get_cycles(); 608 609 mutex_lock(&dlfb->render_mutex); 610 611 aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long)); 612 width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long)); 613 x = aligned_x; 614 615 if ((width <= 0) || 616 (x + width > dlfb->info->var.xres) || 617 (y + height > dlfb->info->var.yres)) { 618 ret = -EINVAL; 619 goto unlock_ret; 620 } 621 622 if (!atomic_read(&dlfb->usb_active)) { 623 ret = 0; 624 goto unlock_ret; 625 } 626 627 urb = dlfb_get_urb(dlfb); 628 if (!urb) { 629 ret = 0; 630 goto unlock_ret; 631 } 632 cmd = urb->transfer_buffer; 633 634 for (i = y; i < y + height ; i++) { 635 const int line_offset = dlfb->info->fix.line_length * i; 636 const int byte_offset = line_offset + (x * BPP); 637 638 if (dlfb_render_hline(dlfb, &urb, 639 (char *) dlfb->info->fix.smem_start, 640 &cmd, byte_offset, width * BPP, 641 &bytes_identical, &bytes_sent)) 642 goto error; 643 } 644 645 if (cmd > (char *) urb->transfer_buffer) { 646 int len; 647 if (cmd < (char *) urb->transfer_buffer + urb->transfer_buffer_length) 648 *cmd++ = 0xAF; 649 /* Send partial buffer remaining before exiting */ 650 len = cmd - (char *) urb->transfer_buffer; 651 dlfb_submit_urb(dlfb, urb, len); 652 bytes_sent += len; 653 } else 654 dlfb_urb_completion(urb); 655 656 error: 657 atomic_add(bytes_sent, &dlfb->bytes_sent); 658 atomic_add(bytes_identical, &dlfb->bytes_identical); 659 atomic_add(width*height*2, &dlfb->bytes_rendered); 660 end_cycles = get_cycles(); 661 atomic_add(((unsigned int) ((end_cycles - start_cycles) 662 >> 10)), /* Kcycles */ 663 &dlfb->cpu_kcycles_used); 664 665 ret = 0; 666 667 unlock_ret: 668 mutex_unlock(&dlfb->render_mutex); 669 return ret; 670 } 671 672 static void dlfb_init_damage(struct dlfb_data *dlfb) 673 { 674 dlfb->damage_x = INT_MAX; 675 dlfb->damage_x2 = 0; 676 dlfb->damage_y = INT_MAX; 677 dlfb->damage_y2 = 0; 678 } 679 680 static void dlfb_damage_work(struct work_struct *w) 681 { 682 struct dlfb_data *dlfb = container_of(w, struct dlfb_data, damage_work); 683 int x, x2, y, y2; 684 685 spin_lock_irq(&dlfb->damage_lock); 686 x = dlfb->damage_x; 687 x2 = dlfb->damage_x2; 688 y = dlfb->damage_y; 689 y2 = dlfb->damage_y2; 690 dlfb_init_damage(dlfb); 691 spin_unlock_irq(&dlfb->damage_lock); 692 693 if (x < x2 && y < y2) 694 dlfb_handle_damage(dlfb, x, y, x2 - x, y2 - y); 695 } 696 697 static void dlfb_offload_damage(struct dlfb_data *dlfb, int x, int y, int width, int height) 698 { 699 unsigned long flags; 700 int x2 = x + width; 701 int y2 = y + height; 702 703 if (x >= x2 || y >= y2) 704 return; 705 706 spin_lock_irqsave(&dlfb->damage_lock, flags); 707 dlfb->damage_x = min(x, dlfb->damage_x); 708 dlfb->damage_x2 = max(x2, dlfb->damage_x2); 709 dlfb->damage_y = min(y, dlfb->damage_y); 710 dlfb->damage_y2 = max(y2, dlfb->damage_y2); 711 spin_unlock_irqrestore(&dlfb->damage_lock, flags); 712 713 schedule_work(&dlfb->damage_work); 714 } 715 716 /* 717 * Path triggered by usermode clients who write to filesystem 718 * e.g. cat filename > /dev/fb1 719 * Not used by X Windows or text-mode console. But useful for testing. 720 * Slow because of extra copy and we must assume all pixels dirty. 721 */ 722 static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf, 723 size_t count, loff_t *ppos) 724 { 725 ssize_t result; 726 struct dlfb_data *dlfb = info->par; 727 u32 offset = (u32) *ppos; 728 729 result = fb_sys_write(info, buf, count, ppos); 730 731 if (result > 0) { 732 int start = max((int)(offset / info->fix.line_length), 0); 733 int lines = min((u32)((result / info->fix.line_length) + 1), 734 (u32)info->var.yres); 735 736 dlfb_handle_damage(dlfb, 0, start, info->var.xres, 737 lines); 738 } 739 740 return result; 741 } 742 743 /* hardware has native COPY command (see libdlo), but not worth it for fbcon */ 744 static void dlfb_ops_copyarea(struct fb_info *info, 745 const struct fb_copyarea *area) 746 { 747 748 struct dlfb_data *dlfb = info->par; 749 750 sys_copyarea(info, area); 751 752 dlfb_offload_damage(dlfb, area->dx, area->dy, 753 area->width, area->height); 754 } 755 756 static void dlfb_ops_imageblit(struct fb_info *info, 757 const struct fb_image *image) 758 { 759 struct dlfb_data *dlfb = info->par; 760 761 sys_imageblit(info, image); 762 763 dlfb_offload_damage(dlfb, image->dx, image->dy, 764 image->width, image->height); 765 } 766 767 static void dlfb_ops_fillrect(struct fb_info *info, 768 const struct fb_fillrect *rect) 769 { 770 struct dlfb_data *dlfb = info->par; 771 772 sys_fillrect(info, rect); 773 774 dlfb_offload_damage(dlfb, rect->dx, rect->dy, rect->width, 775 rect->height); 776 } 777 778 /* 779 * NOTE: fb_defio.c is holding info->fbdefio.mutex 780 * Touching ANY framebuffer memory that triggers a page fault 781 * in fb_defio will cause a deadlock, when it also tries to 782 * grab the same mutex. 783 */ 784 static void dlfb_dpy_deferred_io(struct fb_info *info, struct list_head *pagereflist) 785 { 786 struct fb_deferred_io_pageref *pageref; 787 struct dlfb_data *dlfb = info->par; 788 struct urb *urb; 789 char *cmd; 790 cycles_t start_cycles, end_cycles; 791 int bytes_sent = 0; 792 int bytes_identical = 0; 793 int bytes_rendered = 0; 794 795 mutex_lock(&dlfb->render_mutex); 796 797 if (!fb_defio) 798 goto unlock_ret; 799 800 if (!atomic_read(&dlfb->usb_active)) 801 goto unlock_ret; 802 803 start_cycles = get_cycles(); 804 805 urb = dlfb_get_urb(dlfb); 806 if (!urb) 807 goto unlock_ret; 808 809 cmd = urb->transfer_buffer; 810 811 /* walk the written page list and render each to device */ 812 list_for_each_entry(pageref, pagereflist, list) { 813 if (dlfb_render_hline(dlfb, &urb, (char *) info->fix.smem_start, 814 &cmd, pageref->offset, PAGE_SIZE, 815 &bytes_identical, &bytes_sent)) 816 goto error; 817 bytes_rendered += PAGE_SIZE; 818 } 819 820 if (cmd > (char *) urb->transfer_buffer) { 821 int len; 822 if (cmd < (char *) urb->transfer_buffer + urb->transfer_buffer_length) 823 *cmd++ = 0xAF; 824 /* Send partial buffer remaining before exiting */ 825 len = cmd - (char *) urb->transfer_buffer; 826 dlfb_submit_urb(dlfb, urb, len); 827 bytes_sent += len; 828 } else 829 dlfb_urb_completion(urb); 830 831 error: 832 atomic_add(bytes_sent, &dlfb->bytes_sent); 833 atomic_add(bytes_identical, &dlfb->bytes_identical); 834 atomic_add(bytes_rendered, &dlfb->bytes_rendered); 835 end_cycles = get_cycles(); 836 atomic_add(((unsigned int) ((end_cycles - start_cycles) 837 >> 10)), /* Kcycles */ 838 &dlfb->cpu_kcycles_used); 839 unlock_ret: 840 mutex_unlock(&dlfb->render_mutex); 841 } 842 843 static int dlfb_get_edid(struct dlfb_data *dlfb, char *edid, int len) 844 { 845 int i, ret; 846 char *rbuf; 847 848 rbuf = kmalloc(2, GFP_KERNEL); 849 if (!rbuf) 850 return 0; 851 852 for (i = 0; i < len; i++) { 853 ret = usb_control_msg(dlfb->udev, 854 usb_rcvctrlpipe(dlfb->udev, 0), 0x02, 855 (0x80 | (0x02 << 5)), i << 8, 0xA1, 856 rbuf, 2, USB_CTRL_GET_TIMEOUT); 857 if (ret < 2) { 858 dev_err(&dlfb->udev->dev, 859 "Read EDID byte %d failed: %d\n", i, ret); 860 i--; 861 break; 862 } 863 edid[i] = rbuf[1]; 864 } 865 866 kfree(rbuf); 867 868 return i; 869 } 870 871 static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd, 872 unsigned long arg) 873 { 874 875 struct dlfb_data *dlfb = info->par; 876 877 if (!atomic_read(&dlfb->usb_active)) 878 return 0; 879 880 /* TODO: Update X server to get this from sysfs instead */ 881 if (cmd == DLFB_IOCTL_RETURN_EDID) { 882 void __user *edid = (void __user *)arg; 883 if (copy_to_user(edid, dlfb->edid, dlfb->edid_size)) 884 return -EFAULT; 885 return 0; 886 } 887 888 /* TODO: Help propose a standard fb.h ioctl to report mmap damage */ 889 if (cmd == DLFB_IOCTL_REPORT_DAMAGE) { 890 struct dloarea area; 891 892 if (copy_from_user(&area, (void __user *)arg, 893 sizeof(struct dloarea))) 894 return -EFAULT; 895 896 /* 897 * If we have a damage-aware client, turn fb_defio "off" 898 * To avoid perf imact of unnecessary page fault handling. 899 * Done by resetting the delay for this fb_info to a very 900 * long period. Pages will become writable and stay that way. 901 * Reset to normal value when all clients have closed this fb. 902 */ 903 if (info->fbdefio) 904 info->fbdefio->delay = DL_DEFIO_WRITE_DISABLE; 905 906 if (area.x < 0) 907 area.x = 0; 908 909 if (area.x > info->var.xres) 910 area.x = info->var.xres; 911 912 if (area.y < 0) 913 area.y = 0; 914 915 if (area.y > info->var.yres) 916 area.y = info->var.yres; 917 918 dlfb_handle_damage(dlfb, area.x, area.y, area.w, area.h); 919 } 920 921 return 0; 922 } 923 924 /* taken from vesafb */ 925 static int 926 dlfb_ops_setcolreg(unsigned regno, unsigned red, unsigned green, 927 unsigned blue, unsigned transp, struct fb_info *info) 928 { 929 int err = 0; 930 931 if (regno >= info->cmap.len) 932 return 1; 933 934 if (regno < 16) { 935 if (info->var.red.offset == 10) { 936 /* 1:5:5:5 */ 937 ((u32 *) (info->pseudo_palette))[regno] = 938 ((red & 0xf800) >> 1) | 939 ((green & 0xf800) >> 6) | ((blue & 0xf800) >> 11); 940 } else { 941 /* 0:5:6:5 */ 942 ((u32 *) (info->pseudo_palette))[regno] = 943 ((red & 0xf800)) | 944 ((green & 0xfc00) >> 5) | ((blue & 0xf800) >> 11); 945 } 946 } 947 948 return err; 949 } 950 951 /* 952 * It's common for several clients to have framebuffer open simultaneously. 953 * e.g. both fbcon and X. Makes things interesting. 954 * Assumes caller is holding info->lock (for open and release at least) 955 */ 956 static int dlfb_ops_open(struct fb_info *info, int user) 957 { 958 struct dlfb_data *dlfb = info->par; 959 960 /* 961 * fbcon aggressively connects to first framebuffer it finds, 962 * preventing other clients (X) from working properly. Usually 963 * not what the user wants. Fail by default with option to enable. 964 */ 965 if ((user == 0) && (!console)) 966 return -EBUSY; 967 968 /* If the USB device is gone, we don't accept new opens */ 969 if (dlfb->virtualized) 970 return -ENODEV; 971 972 dlfb->fb_count++; 973 974 if (fb_defio && (info->fbdefio == NULL)) { 975 /* enable defio at last moment if not disabled by client */ 976 977 struct fb_deferred_io *fbdefio; 978 979 fbdefio = kzalloc(sizeof(struct fb_deferred_io), GFP_KERNEL); 980 981 if (fbdefio) { 982 fbdefio->delay = DL_DEFIO_WRITE_DELAY; 983 fbdefio->sort_pagereflist = true; 984 fbdefio->deferred_io = dlfb_dpy_deferred_io; 985 } 986 987 info->fbdefio = fbdefio; 988 fb_deferred_io_init(info); 989 } 990 991 dev_dbg(info->dev, "open, user=%d fb_info=%p count=%d\n", 992 user, info, dlfb->fb_count); 993 994 return 0; 995 } 996 997 static void dlfb_ops_destroy(struct fb_info *info) 998 { 999 struct dlfb_data *dlfb = info->par; 1000 1001 cancel_work_sync(&dlfb->damage_work); 1002 1003 mutex_destroy(&dlfb->render_mutex); 1004 1005 if (info->cmap.len != 0) 1006 fb_dealloc_cmap(&info->cmap); 1007 if (info->monspecs.modedb) 1008 fb_destroy_modedb(info->monspecs.modedb); 1009 vfree(info->screen_base); 1010 1011 fb_destroy_modelist(&info->modelist); 1012 1013 while (!list_empty(&dlfb->deferred_free)) { 1014 struct dlfb_deferred_free *d = list_entry(dlfb->deferred_free.next, struct dlfb_deferred_free, list); 1015 list_del(&d->list); 1016 vfree(d->mem); 1017 kfree(d); 1018 } 1019 vfree(dlfb->backing_buffer); 1020 kfree(dlfb->edid); 1021 dlfb_free_urb_list(dlfb); 1022 usb_put_dev(dlfb->udev); 1023 kfree(dlfb); 1024 1025 /* Assume info structure is freed after this point */ 1026 framebuffer_release(info); 1027 } 1028 1029 /* 1030 * Assumes caller is holding info->lock mutex (for open and release at least) 1031 */ 1032 static int dlfb_ops_release(struct fb_info *info, int user) 1033 { 1034 struct dlfb_data *dlfb = info->par; 1035 1036 dlfb->fb_count--; 1037 1038 if ((dlfb->fb_count == 0) && (info->fbdefio)) { 1039 fb_deferred_io_cleanup(info); 1040 kfree(info->fbdefio); 1041 info->fbdefio = NULL; 1042 } 1043 1044 dev_dbg(info->dev, "release, user=%d count=%d\n", user, dlfb->fb_count); 1045 1046 return 0; 1047 } 1048 1049 /* 1050 * Check whether a video mode is supported by the DisplayLink chip 1051 * We start from monitor's modes, so don't need to filter that here 1052 */ 1053 static int dlfb_is_valid_mode(struct fb_videomode *mode, struct dlfb_data *dlfb) 1054 { 1055 if (mode->xres * mode->yres > dlfb->sku_pixel_limit) 1056 return 0; 1057 1058 return 1; 1059 } 1060 1061 static void dlfb_var_color_format(struct fb_var_screeninfo *var) 1062 { 1063 const struct fb_bitfield red = { 11, 5, 0 }; 1064 const struct fb_bitfield green = { 5, 6, 0 }; 1065 const struct fb_bitfield blue = { 0, 5, 0 }; 1066 1067 var->bits_per_pixel = 16; 1068 var->red = red; 1069 var->green = green; 1070 var->blue = blue; 1071 } 1072 1073 static int dlfb_ops_check_var(struct fb_var_screeninfo *var, 1074 struct fb_info *info) 1075 { 1076 struct fb_videomode mode; 1077 struct dlfb_data *dlfb = info->par; 1078 1079 /* set device-specific elements of var unrelated to mode */ 1080 dlfb_var_color_format(var); 1081 1082 fb_var_to_videomode(&mode, var); 1083 1084 if (!dlfb_is_valid_mode(&mode, dlfb)) 1085 return -EINVAL; 1086 1087 return 0; 1088 } 1089 1090 static int dlfb_ops_set_par(struct fb_info *info) 1091 { 1092 struct dlfb_data *dlfb = info->par; 1093 int result; 1094 u16 *pix_framebuffer; 1095 int i; 1096 struct fb_var_screeninfo fvs; 1097 u32 line_length = info->var.xres * (info->var.bits_per_pixel / 8); 1098 1099 /* clear the activate field because it causes spurious miscompares */ 1100 fvs = info->var; 1101 fvs.activate = 0; 1102 fvs.vmode &= ~FB_VMODE_SMOOTH_XPAN; 1103 1104 if (!memcmp(&dlfb->current_mode, &fvs, sizeof(struct fb_var_screeninfo))) 1105 return 0; 1106 1107 result = dlfb_realloc_framebuffer(dlfb, info, info->var.yres * line_length); 1108 if (result) 1109 return result; 1110 1111 result = dlfb_set_video_mode(dlfb, &info->var); 1112 1113 if (result) 1114 return result; 1115 1116 dlfb->current_mode = fvs; 1117 info->fix.line_length = line_length; 1118 1119 if (dlfb->fb_count == 0) { 1120 1121 /* paint greenscreen */ 1122 1123 pix_framebuffer = (u16 *) info->screen_base; 1124 for (i = 0; i < info->fix.smem_len / 2; i++) 1125 pix_framebuffer[i] = 0x37e6; 1126 } 1127 1128 dlfb_handle_damage(dlfb, 0, 0, info->var.xres, info->var.yres); 1129 1130 return 0; 1131 } 1132 1133 /* To fonzi the jukebox (e.g. make blanking changes take effect) */ 1134 static char *dlfb_dummy_render(char *buf) 1135 { 1136 *buf++ = 0xAF; 1137 *buf++ = 0x6A; /* copy */ 1138 *buf++ = 0x00; /* from address*/ 1139 *buf++ = 0x00; 1140 *buf++ = 0x00; 1141 *buf++ = 0x01; /* one pixel */ 1142 *buf++ = 0x00; /* to address */ 1143 *buf++ = 0x00; 1144 *buf++ = 0x00; 1145 return buf; 1146 } 1147 1148 /* 1149 * In order to come back from full DPMS off, we need to set the mode again 1150 */ 1151 static int dlfb_ops_blank(int blank_mode, struct fb_info *info) 1152 { 1153 struct dlfb_data *dlfb = info->par; 1154 char *bufptr; 1155 struct urb *urb; 1156 1157 dev_dbg(info->dev, "blank, mode %d --> %d\n", 1158 dlfb->blank_mode, blank_mode); 1159 1160 if ((dlfb->blank_mode == FB_BLANK_POWERDOWN) && 1161 (blank_mode != FB_BLANK_POWERDOWN)) { 1162 1163 /* returning from powerdown requires a fresh modeset */ 1164 dlfb_set_video_mode(dlfb, &info->var); 1165 } 1166 1167 urb = dlfb_get_urb(dlfb); 1168 if (!urb) 1169 return 0; 1170 1171 bufptr = (char *) urb->transfer_buffer; 1172 bufptr = dlfb_vidreg_lock(bufptr); 1173 bufptr = dlfb_blanking(bufptr, blank_mode); 1174 bufptr = dlfb_vidreg_unlock(bufptr); 1175 1176 /* seems like a render op is needed to have blank change take effect */ 1177 bufptr = dlfb_dummy_render(bufptr); 1178 1179 dlfb_submit_urb(dlfb, urb, bufptr - 1180 (char *) urb->transfer_buffer); 1181 1182 dlfb->blank_mode = blank_mode; 1183 1184 return 0; 1185 } 1186 1187 static const struct fb_ops dlfb_ops = { 1188 .owner = THIS_MODULE, 1189 .fb_read = fb_sys_read, 1190 .fb_write = dlfb_ops_write, 1191 .fb_setcolreg = dlfb_ops_setcolreg, 1192 .fb_fillrect = dlfb_ops_fillrect, 1193 .fb_copyarea = dlfb_ops_copyarea, 1194 .fb_imageblit = dlfb_ops_imageblit, 1195 .fb_mmap = dlfb_ops_mmap, 1196 .fb_ioctl = dlfb_ops_ioctl, 1197 .fb_open = dlfb_ops_open, 1198 .fb_release = dlfb_ops_release, 1199 .fb_blank = dlfb_ops_blank, 1200 .fb_check_var = dlfb_ops_check_var, 1201 .fb_set_par = dlfb_ops_set_par, 1202 .fb_destroy = dlfb_ops_destroy, 1203 }; 1204 1205 1206 static void dlfb_deferred_vfree(struct dlfb_data *dlfb, void *mem) 1207 { 1208 struct dlfb_deferred_free *d = kmalloc(sizeof(struct dlfb_deferred_free), GFP_KERNEL); 1209 if (!d) 1210 return; 1211 d->mem = mem; 1212 list_add(&d->list, &dlfb->deferred_free); 1213 } 1214 1215 /* 1216 * Assumes &info->lock held by caller 1217 * Assumes no active clients have framebuffer open 1218 */ 1219 static int dlfb_realloc_framebuffer(struct dlfb_data *dlfb, struct fb_info *info, u32 new_len) 1220 { 1221 u32 old_len = info->fix.smem_len; 1222 const void *old_fb = (const void __force *)info->screen_base; 1223 unsigned char *new_fb; 1224 unsigned char *new_back = NULL; 1225 1226 new_len = PAGE_ALIGN(new_len); 1227 1228 if (new_len > old_len) { 1229 /* 1230 * Alloc system memory for virtual framebuffer 1231 */ 1232 new_fb = vmalloc(new_len); 1233 if (!new_fb) { 1234 dev_err(info->dev, "Virtual framebuffer alloc failed\n"); 1235 return -ENOMEM; 1236 } 1237 memset(new_fb, 0xff, new_len); 1238 1239 if (info->screen_base) { 1240 memcpy(new_fb, old_fb, old_len); 1241 dlfb_deferred_vfree(dlfb, (void __force *)info->screen_base); 1242 } 1243 1244 info->screen_base = (char __iomem *)new_fb; 1245 info->fix.smem_len = new_len; 1246 info->fix.smem_start = (unsigned long) new_fb; 1247 info->flags = udlfb_info_flags; 1248 1249 /* 1250 * Second framebuffer copy to mirror the framebuffer state 1251 * on the physical USB device. We can function without this. 1252 * But with imperfect damage info we may send pixels over USB 1253 * that were, in fact, unchanged - wasting limited USB bandwidth 1254 */ 1255 if (shadow) 1256 new_back = vzalloc(new_len); 1257 if (!new_back) 1258 dev_info(info->dev, 1259 "No shadow/backing buffer allocated\n"); 1260 else { 1261 dlfb_deferred_vfree(dlfb, dlfb->backing_buffer); 1262 dlfb->backing_buffer = new_back; 1263 } 1264 } 1265 return 0; 1266 } 1267 1268 /* 1269 * 1) Get EDID from hw, or use sw default 1270 * 2) Parse into various fb_info structs 1271 * 3) Allocate virtual framebuffer memory to back highest res mode 1272 * 1273 * Parses EDID into three places used by various parts of fbdev: 1274 * fb_var_screeninfo contains the timing of the monitor's preferred mode 1275 * fb_info.monspecs is full parsed EDID info, including monspecs.modedb 1276 * fb_info.modelist is a linked list of all monitor & VESA modes which work 1277 * 1278 * If EDID is not readable/valid, then modelist is all VESA modes, 1279 * monspecs is NULL, and fb_var_screeninfo is set to safe VESA mode 1280 * Returns 0 if successful 1281 */ 1282 static int dlfb_setup_modes(struct dlfb_data *dlfb, 1283 struct fb_info *info, 1284 char *default_edid, size_t default_edid_size) 1285 { 1286 char *edid; 1287 int i, result = 0, tries = 3; 1288 struct device *dev = info->device; 1289 struct fb_videomode *mode; 1290 const struct fb_videomode *default_vmode = NULL; 1291 1292 if (info->dev) { 1293 /* only use mutex if info has been registered */ 1294 mutex_lock(&info->lock); 1295 /* parent device is used otherwise */ 1296 dev = info->dev; 1297 } 1298 1299 edid = kmalloc(EDID_LENGTH, GFP_KERNEL); 1300 if (!edid) { 1301 result = -ENOMEM; 1302 goto error; 1303 } 1304 1305 fb_destroy_modelist(&info->modelist); 1306 memset(&info->monspecs, 0, sizeof(info->monspecs)); 1307 1308 /* 1309 * Try to (re)read EDID from hardware first 1310 * EDID data may return, but not parse as valid 1311 * Try again a few times, in case of e.g. analog cable noise 1312 */ 1313 while (tries--) { 1314 1315 i = dlfb_get_edid(dlfb, edid, EDID_LENGTH); 1316 1317 if (i >= EDID_LENGTH) 1318 fb_edid_to_monspecs(edid, &info->monspecs); 1319 1320 if (info->monspecs.modedb_len > 0) { 1321 dlfb->edid = edid; 1322 dlfb->edid_size = i; 1323 break; 1324 } 1325 } 1326 1327 /* If that fails, use a previously returned EDID if available */ 1328 if (info->monspecs.modedb_len == 0) { 1329 dev_err(dev, "Unable to get valid EDID from device/display\n"); 1330 1331 if (dlfb->edid) { 1332 fb_edid_to_monspecs(dlfb->edid, &info->monspecs); 1333 if (info->monspecs.modedb_len > 0) 1334 dev_err(dev, "Using previously queried EDID\n"); 1335 } 1336 } 1337 1338 /* If that fails, use the default EDID we were handed */ 1339 if (info->monspecs.modedb_len == 0) { 1340 if (default_edid_size >= EDID_LENGTH) { 1341 fb_edid_to_monspecs(default_edid, &info->monspecs); 1342 if (info->monspecs.modedb_len > 0) { 1343 memcpy(edid, default_edid, default_edid_size); 1344 dlfb->edid = edid; 1345 dlfb->edid_size = default_edid_size; 1346 dev_err(dev, "Using default/backup EDID\n"); 1347 } 1348 } 1349 } 1350 1351 /* If we've got modes, let's pick a best default mode */ 1352 if (info->monspecs.modedb_len > 0) { 1353 1354 for (i = 0; i < info->monspecs.modedb_len; i++) { 1355 mode = &info->monspecs.modedb[i]; 1356 if (dlfb_is_valid_mode(mode, dlfb)) { 1357 fb_add_videomode(mode, &info->modelist); 1358 } else { 1359 dev_dbg(dev, "Specified mode %dx%d too big\n", 1360 mode->xres, mode->yres); 1361 if (i == 0) 1362 /* if we've removed top/best mode */ 1363 info->monspecs.misc 1364 &= ~FB_MISC_1ST_DETAIL; 1365 } 1366 } 1367 1368 default_vmode = fb_find_best_display(&info->monspecs, 1369 &info->modelist); 1370 } 1371 1372 /* If everything else has failed, fall back to safe default mode */ 1373 if (default_vmode == NULL) { 1374 1375 struct fb_videomode fb_vmode = {0}; 1376 1377 /* 1378 * Add the standard VESA modes to our modelist 1379 * Since we don't have EDID, there may be modes that 1380 * overspec monitor and/or are incorrect aspect ratio, etc. 1381 * But at least the user has a chance to choose 1382 */ 1383 for (i = 0; i < VESA_MODEDB_SIZE; i++) { 1384 mode = (struct fb_videomode *)&vesa_modes[i]; 1385 if (dlfb_is_valid_mode(mode, dlfb)) 1386 fb_add_videomode(mode, &info->modelist); 1387 else 1388 dev_dbg(dev, "VESA mode %dx%d too big\n", 1389 mode->xres, mode->yres); 1390 } 1391 1392 /* 1393 * default to resolution safe for projectors 1394 * (since they are most common case without EDID) 1395 */ 1396 fb_vmode.xres = 800; 1397 fb_vmode.yres = 600; 1398 fb_vmode.refresh = 60; 1399 default_vmode = fb_find_nearest_mode(&fb_vmode, 1400 &info->modelist); 1401 } 1402 1403 /* If we have good mode and no active clients*/ 1404 if ((default_vmode != NULL) && (dlfb->fb_count == 0)) { 1405 1406 fb_videomode_to_var(&info->var, default_vmode); 1407 dlfb_var_color_format(&info->var); 1408 1409 /* 1410 * with mode size info, we can now alloc our framebuffer. 1411 */ 1412 memcpy(&info->fix, &dlfb_fix, sizeof(dlfb_fix)); 1413 } else 1414 result = -EINVAL; 1415 1416 error: 1417 if (edid && (dlfb->edid != edid)) 1418 kfree(edid); 1419 1420 if (info->dev) 1421 mutex_unlock(&info->lock); 1422 1423 return result; 1424 } 1425 1426 static ssize_t metrics_bytes_rendered_show(struct device *fbdev, 1427 struct device_attribute *a, char *buf) { 1428 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1429 struct dlfb_data *dlfb = fb_info->par; 1430 return sysfs_emit(buf, "%u\n", 1431 atomic_read(&dlfb->bytes_rendered)); 1432 } 1433 1434 static ssize_t metrics_bytes_identical_show(struct device *fbdev, 1435 struct device_attribute *a, char *buf) { 1436 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1437 struct dlfb_data *dlfb = fb_info->par; 1438 return sysfs_emit(buf, "%u\n", 1439 atomic_read(&dlfb->bytes_identical)); 1440 } 1441 1442 static ssize_t metrics_bytes_sent_show(struct device *fbdev, 1443 struct device_attribute *a, char *buf) { 1444 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1445 struct dlfb_data *dlfb = fb_info->par; 1446 return sysfs_emit(buf, "%u\n", 1447 atomic_read(&dlfb->bytes_sent)); 1448 } 1449 1450 static ssize_t metrics_cpu_kcycles_used_show(struct device *fbdev, 1451 struct device_attribute *a, char *buf) { 1452 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1453 struct dlfb_data *dlfb = fb_info->par; 1454 return sysfs_emit(buf, "%u\n", 1455 atomic_read(&dlfb->cpu_kcycles_used)); 1456 } 1457 1458 static ssize_t edid_show( 1459 struct file *filp, 1460 struct kobject *kobj, struct bin_attribute *a, 1461 char *buf, loff_t off, size_t count) { 1462 struct device *fbdev = kobj_to_dev(kobj); 1463 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1464 struct dlfb_data *dlfb = fb_info->par; 1465 1466 if (dlfb->edid == NULL) 1467 return 0; 1468 1469 if ((off >= dlfb->edid_size) || (count > dlfb->edid_size)) 1470 return 0; 1471 1472 if (off + count > dlfb->edid_size) 1473 count = dlfb->edid_size - off; 1474 1475 memcpy(buf, dlfb->edid, count); 1476 1477 return count; 1478 } 1479 1480 static ssize_t edid_store( 1481 struct file *filp, 1482 struct kobject *kobj, struct bin_attribute *a, 1483 char *src, loff_t src_off, size_t src_size) { 1484 struct device *fbdev = kobj_to_dev(kobj); 1485 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1486 struct dlfb_data *dlfb = fb_info->par; 1487 int ret; 1488 1489 /* We only support write of entire EDID at once, no offset*/ 1490 if ((src_size != EDID_LENGTH) || (src_off != 0)) 1491 return -EINVAL; 1492 1493 ret = dlfb_setup_modes(dlfb, fb_info, src, src_size); 1494 if (ret) 1495 return ret; 1496 1497 if (!dlfb->edid || memcmp(src, dlfb->edid, src_size)) 1498 return -EINVAL; 1499 1500 ret = dlfb_ops_set_par(fb_info); 1501 if (ret) 1502 return ret; 1503 1504 return src_size; 1505 } 1506 1507 static ssize_t metrics_reset_store(struct device *fbdev, 1508 struct device_attribute *attr, 1509 const char *buf, size_t count) 1510 { 1511 struct fb_info *fb_info = dev_get_drvdata(fbdev); 1512 struct dlfb_data *dlfb = fb_info->par; 1513 1514 atomic_set(&dlfb->bytes_rendered, 0); 1515 atomic_set(&dlfb->bytes_identical, 0); 1516 atomic_set(&dlfb->bytes_sent, 0); 1517 atomic_set(&dlfb->cpu_kcycles_used, 0); 1518 1519 return count; 1520 } 1521 1522 static const struct bin_attribute edid_attr = { 1523 .attr.name = "edid", 1524 .attr.mode = 0666, 1525 .size = EDID_LENGTH, 1526 .read = edid_show, 1527 .write = edid_store 1528 }; 1529 1530 static const struct device_attribute fb_device_attrs[] = { 1531 __ATTR_RO(metrics_bytes_rendered), 1532 __ATTR_RO(metrics_bytes_identical), 1533 __ATTR_RO(metrics_bytes_sent), 1534 __ATTR_RO(metrics_cpu_kcycles_used), 1535 __ATTR(metrics_reset, S_IWUSR, NULL, metrics_reset_store), 1536 }; 1537 1538 /* 1539 * This is necessary before we can communicate with the display controller. 1540 */ 1541 static int dlfb_select_std_channel(struct dlfb_data *dlfb) 1542 { 1543 int ret; 1544 void *buf; 1545 static const u8 set_def_chn[] = { 1546 0x57, 0xCD, 0xDC, 0xA7, 1547 0x1C, 0x88, 0x5E, 0x15, 1548 0x60, 0xFE, 0xC6, 0x97, 1549 0x16, 0x3D, 0x47, 0xF2 }; 1550 1551 buf = kmemdup(set_def_chn, sizeof(set_def_chn), GFP_KERNEL); 1552 1553 if (!buf) 1554 return -ENOMEM; 1555 1556 ret = usb_control_msg(dlfb->udev, usb_sndctrlpipe(dlfb->udev, 0), 1557 NR_USB_REQUEST_CHANNEL, 1558 (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0, 1559 buf, sizeof(set_def_chn), USB_CTRL_SET_TIMEOUT); 1560 1561 kfree(buf); 1562 1563 return ret; 1564 } 1565 1566 static int dlfb_parse_vendor_descriptor(struct dlfb_data *dlfb, 1567 struct usb_interface *intf) 1568 { 1569 char *desc; 1570 char *buf; 1571 char *desc_end; 1572 int total_len; 1573 1574 buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL); 1575 if (!buf) 1576 return false; 1577 desc = buf; 1578 1579 total_len = usb_get_descriptor(interface_to_usbdev(intf), 1580 0x5f, /* vendor specific */ 1581 0, desc, MAX_VENDOR_DESCRIPTOR_SIZE); 1582 1583 /* if not found, look in configuration descriptor */ 1584 if (total_len < 0) { 1585 if (0 == usb_get_extra_descriptor(intf->cur_altsetting, 1586 0x5f, &desc)) 1587 total_len = (int) desc[0]; 1588 } 1589 1590 if (total_len > 5) { 1591 dev_info(&intf->dev, 1592 "vendor descriptor length: %d data: %11ph\n", 1593 total_len, desc); 1594 1595 if ((desc[0] != total_len) || /* descriptor length */ 1596 (desc[1] != 0x5f) || /* vendor descriptor type */ 1597 (desc[2] != 0x01) || /* version (2 bytes) */ 1598 (desc[3] != 0x00) || 1599 (desc[4] != total_len - 2)) /* length after type */ 1600 goto unrecognized; 1601 1602 desc_end = desc + total_len; 1603 desc += 5; /* the fixed header we've already parsed */ 1604 1605 while (desc < desc_end) { 1606 u8 length; 1607 u16 key; 1608 1609 key = *desc++; 1610 key |= (u16)*desc++ << 8; 1611 length = *desc++; 1612 1613 switch (key) { 1614 case 0x0200: { /* max_area */ 1615 u32 max_area = *desc++; 1616 max_area |= (u32)*desc++ << 8; 1617 max_area |= (u32)*desc++ << 16; 1618 max_area |= (u32)*desc++ << 24; 1619 dev_warn(&intf->dev, 1620 "DL chip limited to %d pixel modes\n", 1621 max_area); 1622 dlfb->sku_pixel_limit = max_area; 1623 break; 1624 } 1625 default: 1626 break; 1627 } 1628 desc += length; 1629 } 1630 } else { 1631 dev_info(&intf->dev, "vendor descriptor not available (%d)\n", 1632 total_len); 1633 } 1634 1635 goto success; 1636 1637 unrecognized: 1638 /* allow udlfb to load for now even if firmware unrecognized */ 1639 dev_err(&intf->dev, "Unrecognized vendor firmware descriptor\n"); 1640 1641 success: 1642 kfree(buf); 1643 return true; 1644 } 1645 1646 static int dlfb_usb_probe(struct usb_interface *intf, 1647 const struct usb_device_id *id) 1648 { 1649 int i; 1650 const struct device_attribute *attr; 1651 struct dlfb_data *dlfb; 1652 struct fb_info *info; 1653 int retval; 1654 struct usb_device *usbdev = interface_to_usbdev(intf); 1655 struct usb_endpoint_descriptor *out; 1656 1657 /* usb initialization */ 1658 dlfb = kzalloc(sizeof(*dlfb), GFP_KERNEL); 1659 if (!dlfb) { 1660 dev_err(&intf->dev, "%s: failed to allocate dlfb\n", __func__); 1661 return -ENOMEM; 1662 } 1663 1664 INIT_LIST_HEAD(&dlfb->deferred_free); 1665 1666 dlfb->udev = usb_get_dev(usbdev); 1667 usb_set_intfdata(intf, dlfb); 1668 1669 retval = usb_find_common_endpoints(intf->cur_altsetting, NULL, &out, NULL, NULL); 1670 if (retval) { 1671 dev_err(&intf->dev, "Device should have at lease 1 bulk endpoint!\n"); 1672 goto error; 1673 } 1674 1675 dev_dbg(&intf->dev, "console enable=%d\n", console); 1676 dev_dbg(&intf->dev, "fb_defio enable=%d\n", fb_defio); 1677 dev_dbg(&intf->dev, "shadow enable=%d\n", shadow); 1678 1679 dlfb->sku_pixel_limit = 2048 * 1152; /* default to maximum */ 1680 1681 if (!dlfb_parse_vendor_descriptor(dlfb, intf)) { 1682 dev_err(&intf->dev, 1683 "firmware not recognized, incompatible device?\n"); 1684 retval = -ENODEV; 1685 goto error; 1686 } 1687 1688 if (pixel_limit) { 1689 dev_warn(&intf->dev, 1690 "DL chip limit of %d overridden to %d\n", 1691 dlfb->sku_pixel_limit, pixel_limit); 1692 dlfb->sku_pixel_limit = pixel_limit; 1693 } 1694 1695 1696 /* allocates framebuffer driver structure, not framebuffer memory */ 1697 info = framebuffer_alloc(0, &dlfb->udev->dev); 1698 if (!info) { 1699 retval = -ENOMEM; 1700 goto error; 1701 } 1702 1703 dlfb->info = info; 1704 info->par = dlfb; 1705 info->pseudo_palette = dlfb->pseudo_palette; 1706 dlfb->ops = dlfb_ops; 1707 info->fbops = &dlfb->ops; 1708 1709 mutex_init(&dlfb->render_mutex); 1710 dlfb_init_damage(dlfb); 1711 spin_lock_init(&dlfb->damage_lock); 1712 INIT_WORK(&dlfb->damage_work, dlfb_damage_work); 1713 1714 INIT_LIST_HEAD(&info->modelist); 1715 1716 if (!dlfb_alloc_urb_list(dlfb, WRITES_IN_FLIGHT, MAX_TRANSFER)) { 1717 retval = -ENOMEM; 1718 dev_err(&intf->dev, "unable to allocate urb list\n"); 1719 goto error; 1720 } 1721 1722 /* We don't register a new USB class. Our client interface is dlfbev */ 1723 1724 retval = fb_alloc_cmap(&info->cmap, 256, 0); 1725 if (retval < 0) { 1726 dev_err(info->device, "cmap allocation failed: %d\n", retval); 1727 goto error; 1728 } 1729 1730 retval = dlfb_setup_modes(dlfb, info, NULL, 0); 1731 if (retval != 0) { 1732 dev_err(info->device, 1733 "unable to find common mode for display and adapter\n"); 1734 goto error; 1735 } 1736 1737 /* ready to begin using device */ 1738 1739 atomic_set(&dlfb->usb_active, 1); 1740 dlfb_select_std_channel(dlfb); 1741 1742 dlfb_ops_check_var(&info->var, info); 1743 retval = dlfb_ops_set_par(info); 1744 if (retval) 1745 goto error; 1746 1747 retval = register_framebuffer(info); 1748 if (retval < 0) { 1749 dev_err(info->device, "unable to register framebuffer: %d\n", 1750 retval); 1751 goto error; 1752 } 1753 1754 for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) { 1755 attr = &fb_device_attrs[i]; 1756 retval = device_create_file(info->dev, attr); 1757 if (retval) 1758 dev_warn(info->device, 1759 "failed to create '%s' attribute: %d\n", 1760 attr->attr.name, retval); 1761 } 1762 1763 retval = device_create_bin_file(info->dev, &edid_attr); 1764 if (retval) 1765 dev_warn(info->device, "failed to create '%s' attribute: %d\n", 1766 edid_attr.attr.name, retval); 1767 1768 dev_info(info->device, 1769 "%s is DisplayLink USB device (%dx%d, %dK framebuffer memory)\n", 1770 dev_name(info->dev), info->var.xres, info->var.yres, 1771 ((dlfb->backing_buffer) ? 1772 info->fix.smem_len * 2 : info->fix.smem_len) >> 10); 1773 return 0; 1774 1775 error: 1776 if (dlfb->info) { 1777 dlfb_ops_destroy(dlfb->info); 1778 } else { 1779 usb_put_dev(dlfb->udev); 1780 kfree(dlfb); 1781 } 1782 return retval; 1783 } 1784 1785 static void dlfb_usb_disconnect(struct usb_interface *intf) 1786 { 1787 struct dlfb_data *dlfb; 1788 struct fb_info *info; 1789 int i; 1790 1791 dlfb = usb_get_intfdata(intf); 1792 info = dlfb->info; 1793 1794 dev_dbg(&intf->dev, "USB disconnect starting\n"); 1795 1796 /* we virtualize until all fb clients release. Then we free */ 1797 dlfb->virtualized = true; 1798 1799 /* When non-active we'll update virtual framebuffer, but no new urbs */ 1800 atomic_set(&dlfb->usb_active, 0); 1801 1802 /* this function will wait for all in-flight urbs to complete */ 1803 dlfb_free_urb_list(dlfb); 1804 1805 /* remove udlfb's sysfs interfaces */ 1806 for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) 1807 device_remove_file(info->dev, &fb_device_attrs[i]); 1808 device_remove_bin_file(info->dev, &edid_attr); 1809 1810 unregister_framebuffer(info); 1811 } 1812 1813 static struct usb_driver dlfb_driver = { 1814 .name = "udlfb", 1815 .probe = dlfb_usb_probe, 1816 .disconnect = dlfb_usb_disconnect, 1817 .id_table = id_table, 1818 }; 1819 1820 module_usb_driver(dlfb_driver); 1821 1822 static void dlfb_urb_completion(struct urb *urb) 1823 { 1824 struct urb_node *unode = urb->context; 1825 struct dlfb_data *dlfb = unode->dlfb; 1826 unsigned long flags; 1827 1828 switch (urb->status) { 1829 case 0: 1830 /* success */ 1831 break; 1832 case -ECONNRESET: 1833 case -ENOENT: 1834 case -ESHUTDOWN: 1835 /* sync/async unlink faults aren't errors */ 1836 break; 1837 default: 1838 dev_err(&dlfb->udev->dev, 1839 "%s - nonzero write bulk status received: %d\n", 1840 __func__, urb->status); 1841 atomic_set(&dlfb->lost_pixels, 1); 1842 break; 1843 } 1844 1845 urb->transfer_buffer_length = dlfb->urbs.size; /* reset to actual */ 1846 1847 spin_lock_irqsave(&dlfb->urbs.lock, flags); 1848 list_add_tail(&unode->entry, &dlfb->urbs.list); 1849 dlfb->urbs.available++; 1850 spin_unlock_irqrestore(&dlfb->urbs.lock, flags); 1851 1852 up(&dlfb->urbs.limit_sem); 1853 } 1854 1855 static void dlfb_free_urb_list(struct dlfb_data *dlfb) 1856 { 1857 int count = dlfb->urbs.count; 1858 struct list_head *node; 1859 struct urb_node *unode; 1860 struct urb *urb; 1861 1862 /* keep waiting and freeing, until we've got 'em all */ 1863 while (count--) { 1864 down(&dlfb->urbs.limit_sem); 1865 1866 spin_lock_irq(&dlfb->urbs.lock); 1867 1868 node = dlfb->urbs.list.next; /* have reserved one with sem */ 1869 list_del_init(node); 1870 1871 spin_unlock_irq(&dlfb->urbs.lock); 1872 1873 unode = list_entry(node, struct urb_node, entry); 1874 urb = unode->urb; 1875 1876 /* Free each separately allocated piece */ 1877 usb_free_coherent(urb->dev, dlfb->urbs.size, 1878 urb->transfer_buffer, urb->transfer_dma); 1879 usb_free_urb(urb); 1880 kfree(node); 1881 } 1882 1883 dlfb->urbs.count = 0; 1884 } 1885 1886 static int dlfb_alloc_urb_list(struct dlfb_data *dlfb, int count, size_t size) 1887 { 1888 struct urb *urb; 1889 struct urb_node *unode; 1890 char *buf; 1891 size_t wanted_size = count * size; 1892 1893 spin_lock_init(&dlfb->urbs.lock); 1894 1895 retry: 1896 dlfb->urbs.size = size; 1897 INIT_LIST_HEAD(&dlfb->urbs.list); 1898 1899 sema_init(&dlfb->urbs.limit_sem, 0); 1900 dlfb->urbs.count = 0; 1901 dlfb->urbs.available = 0; 1902 1903 while (dlfb->urbs.count * size < wanted_size) { 1904 unode = kzalloc(sizeof(*unode), GFP_KERNEL); 1905 if (!unode) 1906 break; 1907 unode->dlfb = dlfb; 1908 1909 urb = usb_alloc_urb(0, GFP_KERNEL); 1910 if (!urb) { 1911 kfree(unode); 1912 break; 1913 } 1914 unode->urb = urb; 1915 1916 buf = usb_alloc_coherent(dlfb->udev, size, GFP_KERNEL, 1917 &urb->transfer_dma); 1918 if (!buf) { 1919 kfree(unode); 1920 usb_free_urb(urb); 1921 if (size > PAGE_SIZE) { 1922 size /= 2; 1923 dlfb_free_urb_list(dlfb); 1924 goto retry; 1925 } 1926 break; 1927 } 1928 1929 /* urb->transfer_buffer_length set to actual before submit */ 1930 usb_fill_bulk_urb(urb, dlfb->udev, usb_sndbulkpipe(dlfb->udev, 1), 1931 buf, size, dlfb_urb_completion, unode); 1932 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 1933 1934 list_add_tail(&unode->entry, &dlfb->urbs.list); 1935 1936 up(&dlfb->urbs.limit_sem); 1937 dlfb->urbs.count++; 1938 dlfb->urbs.available++; 1939 } 1940 1941 return dlfb->urbs.count; 1942 } 1943 1944 static struct urb *dlfb_get_urb(struct dlfb_data *dlfb) 1945 { 1946 int ret; 1947 struct list_head *entry; 1948 struct urb_node *unode; 1949 1950 /* Wait for an in-flight buffer to complete and get re-queued */ 1951 ret = down_timeout(&dlfb->urbs.limit_sem, GET_URB_TIMEOUT); 1952 if (ret) { 1953 atomic_set(&dlfb->lost_pixels, 1); 1954 dev_warn(&dlfb->udev->dev, 1955 "wait for urb interrupted: %d available: %d\n", 1956 ret, dlfb->urbs.available); 1957 return NULL; 1958 } 1959 1960 spin_lock_irq(&dlfb->urbs.lock); 1961 1962 BUG_ON(list_empty(&dlfb->urbs.list)); /* reserved one with limit_sem */ 1963 entry = dlfb->urbs.list.next; 1964 list_del_init(entry); 1965 dlfb->urbs.available--; 1966 1967 spin_unlock_irq(&dlfb->urbs.lock); 1968 1969 unode = list_entry(entry, struct urb_node, entry); 1970 return unode->urb; 1971 } 1972 1973 static int dlfb_submit_urb(struct dlfb_data *dlfb, struct urb *urb, size_t len) 1974 { 1975 int ret; 1976 1977 BUG_ON(len > dlfb->urbs.size); 1978 1979 urb->transfer_buffer_length = len; /* set to actual payload len */ 1980 ret = usb_submit_urb(urb, GFP_KERNEL); 1981 if (ret) { 1982 dlfb_urb_completion(urb); /* because no one else will */ 1983 atomic_set(&dlfb->lost_pixels, 1); 1984 dev_err(&dlfb->udev->dev, "submit urb error: %d\n", ret); 1985 } 1986 return ret; 1987 } 1988 1989 module_param(console, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); 1990 MODULE_PARM_DESC(console, "Allow fbcon to open framebuffer"); 1991 1992 module_param(fb_defio, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); 1993 MODULE_PARM_DESC(fb_defio, "Page fault detection of mmap writes"); 1994 1995 module_param(shadow, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); 1996 MODULE_PARM_DESC(shadow, "Shadow vid mem. Disable to save mem but lose perf"); 1997 1998 module_param(pixel_limit, int, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); 1999 MODULE_PARM_DESC(pixel_limit, "Force limit on max mode (in x*y pixels)"); 2000 2001 MODULE_AUTHOR("Roberto De Ioris <roberto@unbit.it>, " 2002 "Jaya Kumar <jayakumar.lkml@gmail.com>, " 2003 "Bernie Thompson <bernie@plugable.com>"); 2004 MODULE_DESCRIPTION("DisplayLink kernel framebuffer driver"); 2005 MODULE_LICENSE("GPL"); 2006 2007